Background and aims: During endoscopy the stomach is considered to rise at the level of the 'gastric' folds; however, anatomical studies have demonstrated that the proximal gastric folds may in fact be esophageal. This prospective study was designed to assess the histopathology of endoscopically visible proximal gastric folds in patients with gastroesophageal reflux disease.
Methods: 35 consecutive patients (20 males) with gastroesophageal reflux disease underwent video endoscopy, including biopsy sampling from the endoscopically visible esophagogastric junction (0 cm, 0.5 cm and 1.0 cm distal to the rise of gastric folds and 0.5 cm and 1.0 cm proximal to it). Endoscopy was digitally recorded and reviewed for assignment of biopsy level. Columnar-lined esophagus and esophagitis were cataloged according to the Paull-Chandrasoma histopathologic classification and the Los Angeles endoscopic classification.
Results: Endoscopy: Normal endoscopic esophagogastric junction was seen in 11 (31%) patients and visible columnar-lined esophagus < or = 0.5 cm in 24 (69%).
Histology: Columnar-lined esophagus extended 1.0 cm in 22.8% of patients and 0.5 cm in 51.4%, distal to the rise of the gastric folds. In all patients columnar-lined esophagus was interposed between squamous epithelium and gastric oxyntic mucosa. Thus, so-called gastric folds contained mucosa of esophageal origin in all patients. Intestinal metaplasia (Barrett esophagus) was detected in eight (22.9%) patients.
Conclusions: Endoscopy cannot exclude histopathologic columnar-lined esophagus within gastric rugae. Thus, visible 'gastric' folds should not be used for definition of the esophagogastric junction but as a reference landmark for biopsy sampling during endoscopy.